The invention is directed to a door or lid which is normally hinged to a washer opening to define a top-loading or a front-loading washer. Conventionally such doors or lids have been made of metal with or without a glass panel through which the interior of the washer can be viewed.
U.S. Pat. No. 4,695,420 granted on Sep. 22, 1987 and assigned to Caterpillar, Inc. makes reference to the desirability of injection molding plastic articles having a variety of complex shapes and sizes including panels and doors of vehicles or equipment enclosures, such as cab doors. Such cab doors were originally manufactured by utilizing a flat rigid frame fabricated from metal to which is unitized a window in what is termed a costly and time-consuming operation. The window or glazing is floated in a soft gasket channel isolated from the frame to reduce shock-loads and thermal stresses induced by varying coefficients of thermal expansion between the metal frame and the glazing/glass panel. It is believed that the process just described is workable because the window panes in all cases are sheets of transparent plastic material, such as polycarbonate and acrylic with the preferred material being a polycarbonate having a silicone hard coat applied thereto to make the polycarbonate glazing or window pane more scratch-resistant. The silicone hard coat on the peripheral edge is removed by sanding or grinding to assure good bonding between the eventually molded frame and the polycarbonate glazing.
With the advent of excellent molding qualities of modern plastic materials, an effort was made to form a door by first manufacturing a pre-shaped pane of transparent glass and subsequently integrally molding the latter into a door frame as the window thereof. Following this process, the window pane was distorted and wavy and the door frame had a tendency to warp. However, by utilizing a high modulus plastic material, such as polyurethane and a shrink-reducing filler material, undesired high temperature rise from exothermic reaction was moderated, particularly when a catalyst was added in sufficient amounts to control the weight of the reaction and the heat evolution. Also, by heating the glass and forming the frame by reaction injection molding, both the frame and the glass window pane thermally contract similarly absent window pane buckle and with bonding of the edges of the glass window pane to the frame.
Glass and specifically tempered glass have heretofore never been provided with an injection molded polymeric/copolymeric frame to form a door or lid, and particularly a washer lid. However, injection-molding polymeric/copolymeric material as an encapsulation or border to form a shelf is well known, as is evidenced by U.S. Pat. No. 5,273,354 granted on Dec. 28, 1993; U.S. Pat. No. 5,362,145 granted on Nov. 8, 1994; U.S. Pat. No. 5,403,084 granted on Apr. 4, 1995; U.S. Pat. No. 5,429,433 granted on Jul. 4, 1995; U.S. Pat. No. 5,441,338 granted on Aug. 15, 1995; U.S. Pat. No. 5,454,638 granted on Oct. 3, 1995; U.S. Pat. No. 5,540,493 granted on Jul. 30, 1996 and U.S. Pat. No. 5,735,589 granted on Apr. 7, 1998.
Other patents dealing with glass to which material is injection molded normally include windshields to which a gasket is molded and/or cured in situ so as to encapsulate a marginal peripheral edge of the windshield. Typical of such window assemblies and methods of forming the same are found in such patents as U.S. Pat. No. 4,778,366 granted on Oct. 18, 1998; U.S. Pat. No. 4,688,752 granted on Aug. 25, 1987 and U.S. Pat. No. 4,732,553 granted on Mar. 22, 1988.
Other patents which were located during the search of the instant invention include U.S. Pat. No. 4,543,283 granted on Sep. 22, 1987; U.S. Pat. No. 3,843,982 granted on Oct. 29, 1974; U.S. Pat. No. 6,146,574, granted on Nov. 14, 2000 and U.S. Pat. No. 4,336,301 granted on Jun. 22, 1982.
The present invention is specifically directed to a door or lid for a washer, but contrary to the door of U.S. Pat. No. 4,695,420, the transparent panel is constructed from tempered glass and an open frame-like encapsulation is preferably a polymeric/copolymeric synthetic plastic material in the form of acrylonitrile/styrene/acrylate polymer blended with mica glass beads at a ratio of substantially 70%-30% to 90%-10% by weight, but preferably 80%-20% by weight. The latter specifics of the blended material which is injection molded to form the open frame-like encapsulation achieves a much lower shrink ratio and elasticity, as compared to polypropylene which is normally used in the injection molding of a tempered glass substrate to form a shelf (not a door). Since tempered glass or a similar glass substrate has virtually a zero coefficient of expansion, the same obviously will not expand or contract in relationship to the expansion or contraction of conventional polymeric/copolymeric material, such as polypropylene. Consequently, typical xe2x80x9cweld linesxe2x80x9d created in the injection molded open frame-like encapsulation or border tend to fracture, particularly as such parts experience temperatures varying between xe2x88x9230xc2x0 F. to +104xc2x0 F. However, through the utilization of the specific blended materials latter defined at the ratios stated, such fracture has been essentially eliminated and the washer door or lid of the present invention achieves unexpected longevity, absent deterioration, and aesthetic characteristics at competitive prices, particularly at higher price-ranged washers.
The aesthetics of the washer lid are also enhanced by designing the exterior of the frame-like encapsulation which is exposed to the consumer as a relatively smooth, unbroken surface except as might otherwise be desired by a washer manufacturer who might specify a recess in the outer surface for reception of a decal, label or the like carrying trademark or other information. The interior of the washer lid which is less susceptible to scrutiny because of it being opened essentially only when the washer is being loaded or unloaded is engineered to include structural characteristics necessary for optimum functionality of the washer lid including, for example, an internally stepped relatively thick inner periphery of the frame-like encapsulation which securely grips and reinforces the peripheral edge of the tempered glass panel, an outboard depending peripheral skirt achieving exterior peripheral rigidity of the frame-like encapsulation, an indiscrete handle portion along an underside of a front wall of the encapsulation which is essentially unobservable when the washer lid is closed, a reinforced corner for a switch actuator, and opposite rear corners rigidly supporting hinges which are utilized to hinge the washer lid to an associated washer opening for movement between open and closed positions thereof.
With the above and other objects in view that will hereinafter appear, the nature of the invention will be more clearly understood by reference to the following detailed description, the appended claims and the several views illustrated in the accompanying drawings.